Paper and paper stock and method of producing the same



Patented Nov. 20, 1928.

UNITED STATES PATENT OFFICE.

LEWIS GRAFFLIN, OF SPRINGFIELD, OHIO, ASSIGNOR 'lO BALL BROTHERSCOMPANY, OF MUNCIE, INDIANA, A CORPORATION OF INDIANA.

PAPER AND PAPER STOCK AND METHOD OF PRODUCING THE SAME.

N0 Drawin In the manufacture of paper suitable for use in makingshipping packages it is necessary that such paper be capable ofwithstanding certain stresses specified by the railroads and, in orderto meet such requirements, it has been the custom, heretofore, toproduce such paper from a pulp composed in part of disintegrated scrappaper to which has been added a specified proportion of wood fibremadeby a process yielding a desired proportion of fibre of sufficient lengthand strength.

Such fibre generally reaches the paper manufactured in sheets, commonlyknown as kraft, which are -then disintegrated and added to thedisintegrated mass of scrap paper,a sufiicient quantity of sizingsuch asrosin-being added to make a sufficiently water-proof product.

Kraft has heretofore been produced by digesting and disintegrating woodchips in a sulphate solution, washing away the said solution and mattingthe Washed fibres. The term kraft as used herein is intended to includesuch material now commonly known in the art by that name, and either inpaper or pulp form.

The object of my present invention is to produce a paper having thedesired and necessary characteristics for shipping packa es, from astraw fibre and without the use 0 an added water-proofing ingredient.

To this end I place a sufiicient quantity of straw in a digester, addthereto an aqueous sodium sulphate solution having a strength of about3% Baum, and after closing the digester, introduce steam atapproximately 11 pounds pressure, more or less, maintaining suchpressure for about ninety minutes.

Following the cooking operation the mass is passed through adisintegrator, preferably of a type which will rub the fibres at rightangles to their lengths rather than by beating. When the fibres havebeen thoroughly disintegrated the mass, without draining or washing, maybe immediately mixed with a desired proportion of pulp formed from scrappaper and passed to the paper forming machine, the result being a papercapable of withstanding the prescribed tests for shipping-package,constituents and being sufficiently water-proof without the addition ofthe usual water-proofing ingredients.

Application filed an... 18, 1925. Serial No. 38,105.

If desired, the unwashed mass of digested straw and the digesting liquormay be matted lnto a substitute for kratt to be later disinptegrated andmixed as described above.

straw (as described above) and that for corrugated filler sheets asomewhat lower grade of disintegrated scrap paper may be used.

' It will be understood that in any method of producing wood fiber by adigesting process the capillary bores of the fibers become thoroughlyfilled with the digesting liquor and that, of course, the exteriors ofthe fibers become coated with such liquor. Heretofore the efiluent fromthe digesters has been subject to a thorough washing action for aconsiderable number of hours, the washing proceeding by a constantaddition of :t'resh water and withdrawal of preceding Water so that thedigesting liquor has been thoroughly washed out and away from boththewalls and bores or the fibers.

My present process, unlike prior methods, involves the utilization ofthe fibers, at the wet end of the paper forming machines, in a conditionwhere a substantial quantity of treating liquor is retained inand-around the fibers so that a substantial quantity of the digesterliquor becomes incorporated in the paper product.

I claim as my invention:

1. A paper containing straw fibres and the residue of a weak sodiumsulphate liquor in which the straw has been disintegrated.

2. An ingredient for use in the manufacture of paper, consisting of aweak sodium sulphate liquor, and straw fibers, which have been producedin said liquor.

3. The method of producing paper which pulp, of a pulp composed ofunwashed fibres of straw which have been disintegrated in a weak sodiumsulphate liquor.

4. The method of producing paper which comprises the disintegration ofstrawin a weak sodium sulphate aqueous liquor under comprises thedisintegration of straw in a weak sodium sulphate aqueous liquor underheat of approximately 242 F., and matting the same into sheets whilecontaining a sub- I stantial residue of said liquor.

7. The method of producing paper which comprises the disintegration ofstraw in a weak sodium sulphate aqueous liquor of approximately 3% Baumunder heat of approximately 242 F., and matting the same mto sheetswhile containing a substantial residue of said liquor.

8. The method of producing paper which comprises the disintegration ofstraw in a weak sodium sulphate aqueous liquor under heat, adding thesame to a quantity of pulp suitable for paper, and forming paper fromsuch mixture while containing a substantial residue of said liquor.

9. The method of producing paper which comprises the disintegration ofstraw in a weak sodium sulphate aqueous liquor of approximately 3% Baum,under heat, adding the same to a quantity of pulp suitable for paper,and forming paper from such mixture while containing a substantialresidue of said liquor.

10. The method of producing paper which comprises the disintegration ofstraw in a weak sodium sulphate aqueous liquor under heat ofapproximately 242 F., adding the same to a quantity of pulp suitable forpaper, and formingpaper from such mixture while containing a substantialresidue of said liquor.

11. The method of producing paper which comprises the disintegration ofstraw in a Weak sodium sulphate aqueous liquor of approximately 3% Baumunder heat of approximately 242 F., adding the same to a quantity ofpulp suitable for paper, and forming paper from such mixture whilecontaining a substantial residue of said liquor.

In witness whereof, I have hereunto set my hand at- Spriugfield, Ohio,this 13th day of.

June, A. D. one thousand nine hundred and twenty-five.-

LEWIS GRAFFLIN.

